/**
 * 编码过滤器
 * @author 董一华
 * @since 1.00
 * @version 1.00 
 * 
 * 修订列表： v1.00 2009-11-06 
 * 			修订人：董一华 
 * 			修订内容：初始版本 
 */

package com.zjht.gmcc.bean.util;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class EncodingFilter implements Filter {

	protected String encoding = "GBK";

	protected FilterConfig filterConfig = null;

	protected boolean ignore = true;

	public void init(FilterConfig filterConfig) throws ServletException {
		this.filterConfig = filterConfig;
		this.encoding = filterConfig.getInitParameter("encoding");
		String value = filterConfig.getInitParameter("ignore");
		if (value == null)
			this.ignore = true;
		else if (value.equalsIgnoreCase("true"))
			this.ignore = true;
		else if (value.equalsIgnoreCase("yes"))
			this.ignore = true;
		else
			this.ignore = false;
	}

	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
			throws IOException, ServletException {
		// Conditionally select and set the character encoding to be used
		if (ignore) {
			if (request.getCharacterEncoding() == null) {
				request.setCharacterEncoding(encoding);
			}
			if (response.getCharacterEncoding() == null) {
				response.setCharacterEncoding(encoding);
			}

		}
		// Pass control on to the next filter
		chain.doFilter(request, response);
	}

	protected String selectEncoding(ServletRequest request) {
		return (this.encoding);
	}

	public void destroy() {
		this.encoding = null;
		this.filterConfig = null;
	}
}
